GNWL = General quota waitlist
The General quota is for passengers travelling the full length (or most of the way) of the train's journey, and the General quota is usually the largest quota.
RLWL = Remote Location quota waitlist
On long distance trains, some stations along the route will be designated Remote Location stations, these will be big stations, and mostly where the train...
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will call at the chosen station (and at the destination station) at popular times, it may also be a station that many people will book to (from the originating station), and this can mean that many seats/berths will become available at the remote location station.
Remote Location stations prepare their own reservation chart 2-4 hours before the train is due to arrive/depart from that station, or the evening before in the case of late/very early departures.
RQWL = Request Quota waitlist
Let me give an example (and this is off the top of my head, so unlikely to be a real example).
Let’s say that Dound Jn is allowed 2 Sleeper Class berths on the Mumbai-Bangalore Udyan Express, and these berths are booked, the next person who wants to travel to Bangalore on the same train has to join a Request Quota waitlist, this waitlist will only improve if a person books a Mumbai-Dound ticket from one of the larger quotas, this would leave the seat vacant from Daund, so would allow another person to board at Dound.
So in theory, the person is requesting a berth in case anyone happens to be getting off at Dound.
(the ‘ping’ from the microwave oven tells me my sticky toffee pudding is ready, damn, it’s too hot, I’ll leave it for 10 minutes to cool down)
PQWL = Pooled Quota waitlist
Pooled Quota is basically anything not covered by the other quotas, though the General ad Remote Location quotas take up most berths. (and lately the Tatkal quota).
Pooled quota can include (though not always) Originating station to intermediate station, Intermediate to intermediate, and intermediate to destination station (though it would be separate from remote location quotas).
CKWL = Tatkal quota waitlist
Tatkal quota is just for last chance bookings and in most cases, can only be booked from originating station to destination station, though you can change the boarding station.
(a strange noise draws me to the kitchen, the noise gets louder as I get nearer, "eat me", "eat me", "eat me", it seems to be coming from my sticky toffee pudding )
How fast will the waitlist move?
It’s not easy to predict, and can be different for every train, even trains on the same route.
The first thing a person needs to find out is how many berths are used for that class on that train between the 2 selected stations, to do this, a person needs to check availability for 90 days ahead.
GNWL = General quota waitlist
I’d be unlikely to accept a waitlisted ticket that’s more than 25-30% of the total general quota, even 90 days ahead, and as the time goes down, the acceptable waitlist number comes down, though 10% of the total general quota can still be good even a week before the train.
RLWL = Remote Location quota waitlist
Same as general quota, but total berths available is likely to be a lot less.
RQWL = Request Quota waitlist
It really depends on the train, and the total number of berths used, but in most cases, I probably wouldn’t want a waitlisted ticket.
PQWL = Pooled Quota waitlist
Total berths used for EXACT same train, class and pair of stations is essential info for the pooled quota waitlist, it can be as low as 2 berths, so even a PQWL 1 ticket would be very unlikely to become confirmed, a very tricky waitlist to predict, so a waitlist that’s best avoided in most cases.
CKWL = Tatkal quota waitlist
Always tricky, mainly because the tickets are booked only 1 day before the train will depart, and because the cancellation fees for confirmed tickets are higher than other quotas, so there’s less chance of cancellations, also, there’s no other quotas (foreign tourist quota , VIP quota , Military quota etc.) can come to the rescue of waitlisted passengers (if quotas remain unsold).